Rope-reeving system for hoisting and racking devices.



H. SAWYER.

ROPE REEVING SYSTEM FOR HOISTING AND BACKING DEVICES.

APPLICATION FILED 0CT.2I. 191a.

1,181,171. Patented May 2, 1916.

Q o k N @I s A N I- o f a 1 R} (F a 1 J I I E E; i i i x T w b a N k N Q a Q a 6] WW wtoz WMMW HARRY SAW YER, OF MUSKEGON, MICHIGAN.

ROPE-REEVING SYSTEM FOR HOISTING AND RACKING DEVICES.

Specification of Letters Patent.

Patented May 2, 1916.

Application filed October 21, 1913. Serial No. 796,425.

To all whom it may concern:

Be it known that I, HARRY SAWYER, a citizen of the United States, residing at Muskegon, county of Muskegon, State of Michigan, have made a certain new and useful Invention in Rope-Reeving Systems for Hoisting and Racking Devices, of which the following is a specification.

The invention relates to rope reeving for hoisting and racking devices.

The object of the invention is to provide a system of reeving for the ropes employed for handling grab buckets, tongs or other hoisting devices, which is simple and efficient in operation.

A further object of the invention is to provide a rope reeving arrangement of the nature referred to wherein means are provided to cause the grab bucket, tongs or other hoisting devices to move in a substan tially horizontal line when the trolley traverses its track on a gauntree crane where the hoisting mechanism is stationary.

Other objects of the invention Will appear more fully hereinafter.

The invention consists substantially in the construction, combination, location and relative arrangement of parts, all as will be more fully hereinafter set forth, as shown in the accompanying drawing, and finally pointed out in the appended claims.

Referring to the drawing: Figure 1 is an elevation, parts broken out, of a crane structure showing the application of a rope reeving arrangement embodying the principles of my invention. Fig. 2 is a similar view, somewhat diagrammatic, showing a modified arrangement for carrying out the principles of my invention. Fig. 3 is a detail view of a grab bucket showing the arrangement of hoisting ropes connected thereto.

In cranes for handling grab buckets,tongs or other similar hoisting devices, it is practical, ordinarily, to place the hoisting mechanism on the load trolley, letting the ropes hang directly from the winding drums to the bucket, tongs or other device. This arrangement, however, is not practical in all types of crane structures, as, for instance. in gauntree cranes having long cantaliver arms. In this type of crane structure the cantaliver arms should not be loaded down with the weight of machinery, and in such a crane structure it is necessary to locate the hoisting machinery at some convenient point on the crane structure and to lead the hoisting ropes from the hoisting machinery to the trolley, the latter operating along a track on the crane arm. In such a system as heretofore employed, the rope is led from the drum, around a sheave at one end of the trolley track, thence over a sheave carried by the trolley, then around a sheave in the lower block, or on the grab bucket, tongs or other device, then up over another sheave carried by the trolley, from where it is led to the opposite end of the trolley track and there anchored. This system of reeving 1s well adapted to the use of cranes equipped with an ordinary hoisting hook, but not to a bucket crane, for most buckets are designed so that the ropes must be attached to them and cannot pass around sheaves carried thereby, and back to the trolley.

My present invention has for its special purpose the provision of a rope reeving which is adapted for use in connection with bucket cranes, tongs, hooks or the like and which is eflicient and practical in operation.

In Fig. 1, A is the crane structure which may be adapted to move along a track B. C, 1s a bucket which carries the load, and D, is the bucket trolley which operates along a track E, on the crane arm. The machinery for operating the bucket C is located stationarily, at F, on the crane structure. Located on a separate track H, is a compensating trolley G. The track H, is required to be only one half the length of the track E along which the load trolley moves.

The ropes 1 and 2 are employed for operating the bucket C. The operation of these ropes may be accomplished by various methods and the invention is not to be restricted in that particular. I have shown, however, two methods of operating the rope drums. In Fig. 1 the bucket ropes 1 and 2 are led to separate and independently operated drums. In Fig. 2 they are led to two clutch controlled drums which are operated by the same motor.

It will be seen that if the ropes 1 and 2 were to pass around the sheaves at the end of the crane structure as at 3 and 4, and over the sheaves 5 and 6 in the trolley D, and down to the bucket C, then, if the trolley were allowed to travel to the left the bucket would move downwardly unless some provision is made for taking up the slack in the bucket ropes 1 and 2, at the same time. To prevent this I employ the compensating trolley G which operates along the track H.

The compensating trolley G travels in a direction opposite to that in which the trolley D travels, and it moves through one half the distance. The bucket ropes instead of passing directly from the hoisting drums 7 to and over the guide sheaves 3, 4, pass, first, around sheaves 8, 9, in the compensating trolley G' and thence over the sheaves 3, 4-, and then over the sheaves 5 and G of the load trolley D, and then down to the bucket Various methods may be used for applying power to cause the trolleys D, G, to travel. I do not want to be restricted in this regard but for illustrative purposes I have shown two arrangements for accomplishing this result.

Fig. 1 shows a motor driven drum 10, placed at the right hand end of the crane structure. Two ropes 11 and 12 are attached to this drum so that when one is wound up the other is unwound. The rope 11, leads directly and is secured to the load trolley D, while the rope 12 leads around a sheave 15 in the compensating trolley G and then back to the end of the track H where it is secured to a part 20 on the crane structure.

In Fig. 2 a modified arrangement is shown whereby a sheave 13 is substituted for the winding drum 10 at the right hand end of the crane structure and the rope 14 leads from the load trolley D around this sheave 13 and around the sheave 21 on the compensating trolley G and thence to the end of the track H where it is secured to a post 22 on the crane structure. The winding drum 16 operates two ropes 17 and 18, one of which is unwound when the other is wound up. The rope 17 is attached directly to the compensating trolley G and the rope 18 leads around a sheave 19 and back to the other end of the same trolley. In this case the power is applied to the compensating trolley in both directions.

The operation of the rope reeving above described, is as follows:\Vhen power is applied to the winding drum 10. Fig. 1. to Wind up the rope 12. the rope 11 is unwound. As the rope 12 winds up it causes the bight thereof which contains the sheave 15. to shorten, thereby causing the compensating trolley G to move toward the right, and as the rope 11 unwinds in equal amount at the same time the load trolley moves to the left. The travel of the compensating trolley takes up the slack of the ropes 1, 2, caused by the load trolley moving to the left. and therefore the bucket or other device C, remains at the same height throughout its travel. This is equally true if the operation of the trolleys is reversed.

In the arrangement shown in Fig. 2 the operation is almost the same with the exception that power is applied directly to the compensating trolley.

For the sake of clearness of illustration, the sheaves in both trolleys and at the left hand end of the structure over which the bucket ropes run are shown placed on separate centers. In practice, however, the sheaves would be. of course, placed on the same pin except possibly in the case of the load trolley sheaves 5, (5.

Having now set forth the object and nature of my invention and a construction embodying the principles thereof, what I claim as new and useful, and of my own invention is 1. The combination with a crane structure. of a load trolley operating thereon, a load engaging device, operating ropes connectcd to said load engaging device, guide sheaves mounted on the trolley and over which said ropes operate, hoisting mechanism to which said ropes are connected, means operating independently of said hoisting mechanism for moving said trolley, said ropes arranged into a bight intern'iediate said hoisting mechanism and said trolley, and means for varying the length of said bight as the trolley moves.

2. The combination of a crane structure having a main and supplemental track, a load and a compensating trolley respectively operating on said tracks, hoisting machinery mounted stationarily on the crane structure, guide sheaves respectively carried by the crane structure and said trolleys, a loadcngaging device, operating ropes connected at opposite ends to the hoisting machinery and load engaging device respectively and operating over said sheaves, and means operating independently of said hoisting machinery to move said trolleys in opposite directions.

In a rope reeving system for bucket cranes. the combination of a bucket, a load trolley having sheaves, a track along Which said load trolley moves, sheaves at one end of said track. a compensating trolley having sheaves. bucket operating ropes attached to the bucket and passing over the sheaves in the load trolley, the sheaves at the end of the trolley track, and the sheaves in the compensating trolley, means for operating said ropes, and means for controlling the movements of said loads and compensating trolleys.

4. In a rope reeving system for bucket cranes, the combination of a bucket, a load trolley therefor. a track therefor, a compensating trolley. a separate track for the compensating trolley, ropes for operating said bucket, winding drums therefor, said ropes leading from said drums over sheaves on said compensating trolley and then over sheaves at one end of the load trolley track and then over sheaves on the load trolley, a rope attached to one end of the load trolley and at its other end to a Winding drum,

a rope attached to one end of the compensating trolley track and passing over a sheave on the compensating trolley and thence leading to said Winding drum and means for winding and unwinding said ropes.

5. The combination of a crane structure having an arm, a trolley operating along said arm, hoisting machinery stationarily mounted on the crane structure, a load engaging device, operating ropes connected to the hoisting machinery and load engaging device respectively, guide sheaves on the crane structure and on the trolley respectively over which said ropes operate, movable means comprising a second trolley for engaging said ropes and means operating independently of said hoisting machinery to move said movable means and said first mentioned trolley, respectively, in opposite directions.

In testimony whereof I have hereunto set my hand in the presence of the subscribing Witnesses, on this 14th day of Octoher, A. D. 1913.

HARRY SAWYER.

Witnesses NORMAN WHICHELTO, O'r'ro ALBERT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

